PDFgetX3: a rapid and highly automatable program for processing powder diffraction data into total scattering pair distribution functions

PDFgetX3 is a new software application for converting X-ray powder diffraction data to an atomic pair distribution function (PDF). PDFgetX3 has been designed for ease of use, speed and automated operation. The software can readily process hundreds of X-ray patterns within a few seconds and is thus useful for high-throughput PDF studies that measure numerous data sets as a function of time, temperature or other environmental parameters. In comparison to the preceding programs, PDFgetX3 requires fewer inputs and less user experience and it can be readily adopted by novice users. The live-plotting interactive feature allows the user to assess the effects of calculation parameters and select their optimum values. PDFgetX3 uses an ad hoc data correction method, where the slowly changing structure-independent signal is filtered out to obtain coherent X-ray intensities that contain structure informa­tion. The output from PDFgetX3 has been verified by processing experimental PDFs from inorganic, organic and nanosized samples and comparing them with their counterparts from a previous established software. In spite of the different algorithm, the obtained PDFs were nearly identical and yielded highly similar results when used in structure refinement. PDFgetX3 is written in the Python language and features a well documented reusable code base. The software can be used either as a standalone application or as a library of PDF processing functions that can be called from other Python scripts. The software is free for open academic research but requires paid license for commercial use.

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